The invention relates to a method for determining the torque on the crankshaft of an internal combustion engine.
The torque on the crankshaft of an internal combustion engine is determined by means of the value of the mass volumetric efficiency. To do this, the time profile of the mass volumetric efficiency itself is determined by means of an estimate. The torque is then determined in accordance with this estimate.
It is the object of the present invention to provide a method with which the torque, which is generated by an internal combustion engine, can be determined more precisely in particular in non-steady engine operating states.
In a method for determining the torque of the crankshaft of an internal combustion engine, the intake work of the cylinder in the respective working cycle during the intake period, the compression work of the cylinder in the respective working cycle during the compression period, the combustion work of the cylinder in the respective working cycle during the combustion period and the expulsion work of the cylinder in the respective working cycle during the exhaust period are determined, and the work on the crankshaft in the respective working cycle is determined therefrom.
As a result, the work applied by the engine pistons to the crankshaft can be determined in synchronism with the working cycle even under non-steady-state operating conditions.
This precise determination of the time profile of the torque provides the possibility of considerably improving the method of controlling internal combustion engines in that the torque which is available at the crankshaft can be determined precisely, and with respect to its time profile under non-steady-state operating conditions.
An exemplary embodiment of the invention is illustrated below on the basis of the accompanying drawings.